[PATCH v4 1/9] block: introduce disk_zone_is_offline()

[Damien Le Moal <dlemoal@kernel.org>]

Introduce the helper function disk_zone_is_offline() for testing if a zone
of a gendisk has the offline condition. The zone to test is identified
using a sector number that must belong to the target zone to check.

Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
---
 block/blk-zoned.c      | 16 ++++++++++++++++
 include/linux/blkdev.h |  9 +++++++++
 2 files changed, 25 insertions(+)

diff --git a/block/blk-zoned.c b/block/blk-zoned.c
index 19268afb8752..44010be6876a 100644
--- a/block/blk-zoned.c
+++ b/block/blk-zoned.c
@@ -292,6 +292,22 @@ static bool disk_zone_is_seq(struct gendisk *disk, sector_t sector)
 	return !blk_zstate_is_conv(zs);
 }
 
+/**
+ * disk_zone_is_offline - check if a sector belongs to an offline zone
+ * @disk:	gendisk to check
+ * @sector:	sector number
+ *
+ * Check if @sector on @disk is contained in an offline zone.
+ */
+bool disk_zone_is_offline(struct gendisk *disk, sector_t sector)
+{
+	if (!blk_queue_is_zoned(disk->queue))
+		return false;
+
+	return disk_zone_get_cond(disk, sector) == BLK_ZONE_COND_OFFLINE;
+}
+EXPORT_SYMBOL_GPL(disk_zone_is_offline);
+
 /**
  * bdev_zone_is_seq - check if a sector belongs to a sequential write zone
  * @bdev:       block device to check
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index d003a9d2d1f6..83d88dfe59f5 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -942,6 +942,9 @@ static inline unsigned int disk_zone_capacity(struct gendisk *disk,
 		return disk->last_zone_capacity;
 	return disk->zone_capacity;
 }
+
+bool disk_zone_is_offline(struct gendisk *disk, sector_t sector);
+
 static inline unsigned int bdev_zone_capacity(struct block_device *bdev,
 					      sector_t pos)
 {
@@ -956,6 +959,12 @@ static inline unsigned int disk_nr_zones(struct gendisk *disk)
 	return 0;
 }
 
+static inline bool disk_zone_is_offline(struct gendisk *disk,
+					sector_t sector)
+{
+	return false;
+}
+
 static inline bool bdev_zone_is_seq(struct block_device *bdev, sector_t sector)
 {
 	return false;
-- 
2.55.0